In general, neutral gray or off-white backdrops tend to work the best. I use a commercially-made gradient background that's printed on stiff but flexible plastic. You can also print your own on paper (Kinko's has large-format printers) for a lot less money. Here's a simple gradient background JPEG file that can be printed onto a large sheet of paper:
(After clicking on this link above, right-click on the picture that's displayed and save it on your computer. Then you can use use that saved image file to take to Kinko's for printing.
Also, you're missing a decimal point in your camera specs. It's a 5.0 megapixel camera, not 50.
When the going gets weird, the weird turn pro. - Hunter S. Thompson
When the weird get going, they start their own forum. - Vaughn McMillan